def minimax(player, depth, alpha, beta):
    # If the game is over or we've reached the maximum depth, return a score for the board
    if depth == 0 or check_win("black") or check_win("red") or not check_moves_left():
        return check_curr_score(), -1, -1  # Return the score and an invalid move (-1, -1)

    best_score = -float('inf') if player == "black" else float('inf')
    best_row, best_col = -1, -1

    # Explore all possible columns for the next move
    for col in range(7):
        if is_valid_move(col):  # If the column is valid, try a move
            row = check_column_depth(col)  # Get the next available row
            place_player(player, row, col)  # Make the move on the board
            score, _, _ = minimax("red" if player == "black" else "black", depth-1, alpha, beta)  # Recursively call minimax

            # Undo the move after evaluating
            board[row][col] = "-"

            # Update the best score and column
            if player == "black" and score > best_score:
                best_score = score
                best_row, best_col = row, col
                alpha = max(alpha, score)
            elif player == "red" and score < best_score:
                best_score = score
                best_row, best_col = row, col
                beta = min(beta, score)

            # Alpha-Beta Pruning
            if alpha >= beta:
                break

    return best_score, best_row, best_col